Partitioned extinguishing chamber with imperforate partition in direct contact with arc runners



June 30, 1964 FEHUNG ETAL 3,139,502

PARTITIONED EXTINGUISHING CHAMBER WITH IMPERFORATE PARTITION IN DIRECT CONTACT WITH ARC RUNNERS Filed April 17, 1961 jm emons: WW

Fig.2

3,139,502 PARTITIONED ExrrNGrnsHrNt; HAMBER wirn IWPERFQRATE PARTITION IN umncr CON- TACT WITH ARC RUNNERS I Heinz Fehling, Mecklenburger Weg, Einfeld, and Arno Treptow, Neurnunster, Germany, assignors to Licentia Patent-Verwaltungs 'G.m.b.H., Frankfurt am Main, Germany Filed Apr. 17, 1961, Ser. No. 103,596 Claims priority, application Germany Apr. 21, 1960 Claims. (Cl. 200-444) The present invention relates to an electric switch.

More particularly, the present invention relates to an arc extinguishing chamber for use in combination with an electric switch.

There .exist are extinguishing chambers incorporating one or more insulating partitions which divide the chamber into a number of longitudinal cells or partial chambers so that an are which is driven into the are extinguishing or quenching chamber is broken up into a plurality of parallel arc portions. generally such that the are extinguishing means, namely, the partitions, are arranged relatively far away from the separating contacts. Thus, the arc does not enter the actual are extinguishing chambers until after it has had an opportunity to develop and after it has already travelled a certain distance along the arc gap formed between the elongated diverging contact surfaces of the contact elemen-ts.

It is, therefore, an object of the present invention to provide an arc extinguishing chamber which overcomes the above disadvantages, and, with this object in view, the present invention resides, basically, in an are extinguishing chamber for use with an electric switch, for eX- ample, a quick-acting direct current switch, wherein at least one longitudinal partition is arranged parallel to the arc, which partition extends directly to the place at which the arc is formed'upon switch opening resulting from the movement of a movable contact. More particularly, the edge portions of the partition which are directed toward the contact surfaces are narrower than, and in direct contact with, the contact surfaces. Moreoventhe partition has a free edge portion which extends generally along the line of movement of the movable contact. Thus, there is stillsufficient place for base points of the arc to form along the contact surfaces on opposite sides of the partition. Above 'the'two separating contacts, there will be at least two relatively narrow partial chambers.

Additional objects and advantages of the present invention will become apparent upon consideration of the following description when taken in conjunction with the accompanying drawings in which:

FIGURE 1 is a side View of an arc extinguishing chamber according to the present invention, the parts being shown partly broken away for purposes of clarity.

FIGURE 2 is a sectional view taken on line 22 of FIGURE 1;

Referring'now to the drawing, the same shows a movable contact 1 which is carried by a resiliently mounted pivot 2. The contact 1 abuts a stationary contact 3 which has a rightwardly extending portion 4 that serves as a contact surface along which one end of an arc formed upon switch opening will run. The contact surface along which the other end of this are will run extends leftwardly as shown at 5, this contact surface being electrically connected with the movable contact 1.

An imperforate insulating partition 6 is arranged immediately above the movable contact 1. The lower edge of this partition, which is directed toward the diverging surfaces 4, 5, and which is preferably beveled as shown at 9, has a configuration mating with that of these contact surfaces 4, 5, and abuts the same. As shown in The arrangement is e 3,139,502 Patented June 30, 1964 FIGURE 1, the lower-most edge portion of the partition 6 extends generally along the line of movement of the movable contact 1.

Two side walls7 and 8 are arranged on opposite sides of the diverging contact surfaces, these walls forming together with the partition 6 two narrow partial chambers 7a, 8a, which are arranged immediately above the place where the arc is formed upon switch opening, into which chambers this arc is driven, at the instant of its formation, by appropriate magnetic blowout coils which are of conventional design and therefore not shown. The

width of. each of the two chambers 7a, 8a, is approximately equal to-the thickness of the partition 6.

It has been found'that inspite of the fact that the chambers 7a, 8a, are relatively narrow and located immediately above the contacts, normal magnetic blowing will suffice to drive the are into these chambers. This is facilitated by the above-mentioned beveling of the edge 9.

The are extinguishing chamber further includes two angle pieces 13 carrying upper outside walls 12. Also shown are downwardly extending pointed arc-dividing ele- .ments 10 as well as a further partition 11 which forms a continuation of the partition 6. The arrangement of the entire structure is such that the parts 6, 7, 8, 13 form one component and the parts it), 11, 12, another component. These components, which define the actual arc forming chamber and the arc-quenching chamber, respectively, are readily separable from each other. In this way, the elements of each component may be made of the appropriate material, i.e., the lower component is made of better grade insulating material as, for example, Mycalex, whereas the upper component is made of less expensive material as, for example, asbestos cement.

The are extinguishing chamber according to the present invention is particularly well suited for extinguishing the arcs created during switch opening in heavily inductive circuits having largely varying rates of current rise,

such as is the case in direct current railroad equipment- Thanks to the imperforate partition which extends all the way to the place at which the arc is formed, and due to the fact that the partition abuts the contact surfaces, the

are will be efiiciently cooled from the moment of its inception, as well as during its propagation, throughout its entire length, i.e., from one end to the other. Consequently, the voltage across the arc increases relatively steeply from the very beginning, so that the current will not rise to larger values; instead, the current will drop already 0.5 to 2 milliseconds after contact opening and within a short timeinterval becomes zero.

It will be understood that the above description of the present invention is susceptible to various modifications,

changes, and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.

What is claimed is: p

1. In combination with an electric switch having elongated diverging contact surfaces along which an arc is formed upon switch opening resulting from movement of a movable contact, means forming an arc extinguishing chamber and including at least one longitudinal imperiorate partition arranged parallel to the arc, said partition having edge portions which are narrower than, and in direct contact with, said contact surfaces and a free edge portion which extends generally along the line of movement of said movable contact so that said partition be gins substantially at the place at which said arc is formed upon switch opening.

2. The combination defined in claim 1 wherein said partition as a whole is narrower than said contact surfaces.

3. The combination defined in claim 2 wherein said edge portions of said partition are beveled,

4-. The combination defined in claim 1 wherein said means including said partition form two partial chambers each having a width approximately equal to the thickness of said partition.

5. The combination defined in claim 1 wherein said means including said partition are made of readily separable components forrning, respectively, an arc-forming chamber and an arc-quenching chamber. a

References Cited in the file of this patent UNITED STATES PATENTS Scott Sept. 9, 1947 Seaman Oct. 28, 1947 Scully Nov. 18, 1958 FOREIGN PATENTS France Mar. 14, 1944 

1. IN COMBINATION WITH AN ELECTRIC SWITCH HAVING ELONGATED DIVERGING CONTACT SURFACES ALONG WHICH AN ARC IS FORMED UPON SWITCH OPENING RESULTING FROM MOVEMENT OF A MOVABLE CONTACT, MEANS FORMING AN ARC EXTINGUISHING CHAMBER AND INCLUDING AT LEAST ONE LONGITUDINAL IMPERFORATE PARTITION ARRANGED PARALLEL TO THE ARC, SAID PARTITION HAVING EDGE PORTIONS WHICH ARE NARROWER THAN, AND IN DIRECT CONTACT WITH, SAID CONTACT SURFACES AND A FREE EDGE PORTION WHICH EXTENDS GENERALLY ALONG THE LINE OF MOVEMENT OF SAID MOVABLE CONTACT SO THAT SAID PARTITION BEGINS SUBSTANTIALLY AT THE PLACE AT WHICH SAID ARC IS FORMED UPON SWITCH OPENING. 